This invention relates to a vibration telemetering system and in particular to a vibration measuring system for telemetering any vibration of installations or equipment within a plant.
As is well known, to detect abnormalities in the operation of such plants as nuclear power plants etc., measurements of undesirable vibrations of the equipment in the plant are carried out. In checking for abnormal vibrations, it has heretofore been done by a man patrolling a plant, and using a vibrometer. Namely, a patroller carrying a vibrometer measures the vibrations of installations or equipment within the plant such as pipes, valves, pumps, heat exchanger etc. and compares the measured results with respective tabulated vibration values designating normal states to determine whether or not any abnormalities exist. In this case, a contacting type of vibrometer which is convenient for carrying around is employed, the contacting vibrometer having its detection head electrically connected to the vibrometer, the head being directly pressed against an object to be measured to provide a reading at that time.
As mentioned above, the conventional monitoring operation for vibrations has been made by a man patrolling a plant, so that it is inevitable that certain measurements will be misrecorded, misread, or that certain measurements will be missed altogether. Further, especially in places where there is danger of radiation exposure such as in a nuclear containment vessel of a nuclear power plant, it is disadvantageously difficult to monitor such vibrations since a man can not easily get into the containment vessel.
On the other hand, another method considers vibration sensors which are previously mounted at places to be monitored wherein signals from the sensors are transmitted to a central control room. However, this method is not preferable because of the fact that the places to be monitored actually depend on the status of the apparatus at that time, and because if such sensors were mounted on all the possible places, enormous number of sensors and signal transmission cables would be required.
Furthermore, an article appearing in "Hitachi Hyoron", Vol. 62, No. 9, September 1980 by Nakamura etc. discloses a nuclear reactor acoustic vibration monitoring apparatus developed as a "loose parts monitor" for detecting the generation of abnormal vibrations and loose parts during the early stages thereof while in another section of the article, it separately discloses an inspection system within a nuclear reactor containment vessel which includes a mobile station having mounted thereon a detector such as a TV camera, a trolley chain for pulling the mobile station, a console for remote-controlling the system in its entirety, and a computer for processing the result while checking the equipment in the nuclear reactor containment vessel. As an acoustic emission and vibration detector, a piezo-electric device or an acceleration meter resistant to heat or radiation may be generally employed as disclosed in Japanese Patent Application Laid-open No. 55-151224 which corresponds to the U.S. patent application Ser. No. 36,715, now U.S. Pat. No. 4,304,629. The above article has the disadvantage that in order to measure the vibration of equipment by such a travelling type apparatus, a vibration sensor such as a piezo-electric device has to be mounted on a robot arm and directly pressed against the surface of the equipment.
Japanese Patent Application Laid-Open No. 58-76799 teaches how to make a display corresponding to a surface temperature at a position on a TV picture image corresponding to a measured place of a monitored object in the equipment.